钾硅肥配施对胡麻茎秆碳水化合物及抗倒性的影响

为明确钾硅肥施用对胡麻茎秆碳水化合物主要成分含量及抗倒伏特性的影响,探讨钾硅肥运筹调控胡麻茎秆抗倒伏能力的机制,选用裂区试验设计进行了研究,以两个品种为主处理,三个K2O钾肥用量(K0:不施钾;K1:52.5 kg/hm2;K2:105 kg/hm2)为副处理,两个SiO2硅肥用量(Si0:不施硅;Si1:90 kg/...     

异粒包膜控释肥料氮素释放特性的研究

按照商品控释肥料的核芯肥料之粒级进行混配,利用底喷流化包膜技术制造出异粒包膜控释肥。通过静水培养试验,分别测得不同粒径控释肥料0、1、2、3、4、5、6、7、14、21、28、56 d的氮素释放率,探讨粒径对氮素释放率、膜芯比等的影响。结果表明,随着粒径增加,氮素释放率明显降低,培养1 d,2～3、3～4、4～5 mm粒径控释肥料的氮素释放率依次为26.9%、4.45%、1.26%; 2～3 mm粒径的控释肥料的控释期只有4 d,3～4 mm为28 d,4～5 mm的大于56 d。培养过程,即控释肥料氮素释放过程,前期释放的氮素主要来自3 mm粒径的控释肥料。粒径大小对膜芯比有极显著的影响,膜芯比随着粒径的增加而增加。2～3 mm粒径控释肥料膜芯比比预设的降低15.58%,3～4 mm的降低了4.29%; 而4～5 mm的膜芯比则比设计的增加了5.65％。因此要保证控释肥料产品的质量,核芯肥料的粒级是必须控制的重要因素之一。     

小麦化肥减施与不同轮作方式的周年养分平衡及经济效益分析

[目的]研究小麦化肥减量条件下不同轮作方式土壤养分平衡及经济效益差异,探索适宜陕西关中小麦玉米轮作区的小麦轮作方式,为减少化肥投入,提高农民经济收入提供思路与科学依据.[方法]于2018-2020年在陕西武功镇开展田间试验,随机区组设计.设玉米-小麦轮作农户施肥(CWF)、玉米-小麦轮作推荐施肥(CWR)、绿肥-小麦轮...     

Short-term competition between crop plants and soil microbes for inorganic N fertilizer

Agricultural systems that receive high amounts of inorganic nitrogen (N) fertilizer in the form of either ammonium (NH₄⁺), nitrate (NO₃⁻) or a combination thereof are expected to differ in soil N transformation rates and fates of NH₄⁺ and NO₃⁻. Using ¹⁵N tracer techniques this study examines how crop plants and soil microbes vary in their ability to take up and compete for fertilizer N on a short time scale (hours to days). Single plants of barley (Hordeum vulgare L. cv. Morex) were grown on two agricultural soils in microcosms which received either NH₄⁺, NO₃⁻ or NH₄NO₃. Within each fertilizer treatment traces of ¹⁵NH₄⁺ and ¹⁵NO₃⁻ were added separately. During 8 days of fertilization the fate of fertilizer ¹⁵N into plants, microbial biomass and inorganic soil N pools as well as changes in gross N transformation rates were investigated. One week after fertilization 45-80% of initially applied ¹⁵N was recovered in crop plants compared to only 1-10% in soil microbes, proving that plants were the strongest competitors for fertilizer N. In terms of N uptake soil microbes out-competed plants only during the first 4 h of N application independent of soil and fertilizer N form. Within one day microbial N uptake declined substantially, probably due to carbon limitation. In both soils, plants and soil microbes took up more NO₃⁻ than NH₄⁺ independent of initially applied N form. Surprisingly, no inhibitory effect of NH₄⁺ on the uptake and assimilation of nitrate in both, plants and microbes, was observed, probably because fast nitrification rates led to a swift depletion of the ammonium pool. Compared to plant and microbial NH₄⁺ uptake rates, gross nitrification rates were 3-75-fold higher, indicating that nitrifiers were the strongest competitors for NH₄⁺ in both soils. The rapid conversion of NH₄⁺ to NO₃⁻ and preferential use of NO₃⁻ by soil microbes suggest that in agricultural systems with high inorganic N fertilizer inputs the soil microbial community could adapt to high concentrations of NO₃⁻ and shift towards enhanced reliance on NO₃⁻ for their N supply.     

穴盘育苗基质的养分供应对万寿菊和矮牵牛种苗生长的影响

育苗基质中适量的养分供应是培育优质壮苗的关键.选用东北草炭和蛭石4:1配制基质,运用正交试验设计,加入不同浓度的氮、磷、钾肥料,进行了万寿菊和矮牵牛穴盘育苗研究.结果表明,不同浓度配比氮、磷、钾肥料对两种草花种苗生长的影响不同.低氮中磷钾(O.1kg/m3 N、0.4kg/m3 P2O5、0.4kg/m3K2O)和低氮高磷钾(0.1kg/m3 N、0.8kg/m3 P205、0.8kg/m3 K2O)下,2种草花生长最快,接近或超过进口基质;万寿菊和矮牵牛种苗分别以低N中P高K(N 0.2kg/m3、P205 0.4 kg/m3、K20 0.8kg/m3)和中N高P高Km 0.4kg/m3、P205 0.8kg/m3、K20 0.8kg/m3)育苗效果最好.     

个人所得税改革如何体现效率和公平

经过十多年的运行,中国现行个人所得税在增加财政收入和调节社会财富差距上作出贡献后,其弊病也在不断突出。为了能让个人所得税在国民经济中近一步发挥其重要作用,个人所得税改革势在必行。本文就是围绕这个课题展开研究,通过吸收世界各国税制改革的理论与实践成果,对中国现行个人所得税进行分析,同时提出其改革方向和措施,促进中国个人所得税更加合理,更有效率,更加公平。     

吉林省九台市地力现状与主要作物的施肥情况

通过对吉林省九台市土壤养分现状的调查,明确高产作物施肥模式形成的机理,提出适合九台市的施肥模式。     

初探酵素生物菌肥料对盐碱地水稻生长的影响

探讨了大安市盐碱地施酵素生物菌肥料，采用简塑盘大棚育壮秧，浅翻（ 耙） ，洗盐排碱，配施氮、磷、钾、锌肥，综合防治病虫草害等综合栽培措施，水稻公顷产量获得８ ５００ ｋｇ 以上的丰产技术．其产量结构为每平方米穴数为２５ 穴，每平方米穗数６００ 穗，穗总粒数为８７ 粒，结实率为８９ ％ ，千粒重为２７ ．７ ｋｇ ，产量为８ ５００ ｋｇ．     

钙镁型秸秆生物炭肥缓释性能及其对玉米生长的影响

化肥的一次施用量过大造成面源污染,给生态环境带来了诸多负面影响,功能化生物炭是构建化肥缓释的重要材料,是生物炭基缓释肥开发的一条途径。该研究以玉米秸秆为炭原料,鸡蛋壳为钙原料,基于热解转化技术耦合氮磷的同步富集制备钙镁型秸秆生物炭肥(Ca/Mg-BCF)。通过温度和pH值对Ca/Mg-BCF缓释性能的影响试验、缓释动力学和淋溶模拟试验等,研究了Ca/Mg-BCF的缓释性能;结合表征技术,初步揭示其缓释氮磷的机理;利用盆栽试验考察了该炭肥与传统化肥对玉米生长影响。结果表明:Ca/Mg-BCF对N和P的缓释作用明显优于化肥(CF),Ca/Mg-BCF对N和P的释放率(5.90%和8.68%)在缓释48 h后,分别比CF降低了88.10个百分点和74.22个百分点;淋溶试验证明,Ca/Mg-BCF对N和P的累积释放率呈现缓慢增长的趋势;Ca/Mg-BCF对养分的释放受温度(10～40℃)的影响较小,其对N和P的释放分别在pH值为1～7和3～10之间较为平稳。Ca/Mg-BCF对N和P的缓释性能,主要受多种作用协同控制,包括鸟粪石等晶体的溶解速率、磷酸根的再沉淀、静电吸引以及生物炭的限域效应等...     

大民钾王拌种对玉米的增产效应

用生物肥料——大民钾王对玉米进行拌种栽培试验 ,研究其增产效应 ,结果表明 :玉米果穗的长度、穗行数、单穗粒数、千粒重及籽粒产量均增加。其生理原因是由于大民钾王所含解钾菌能将土壤中的矿物钾、固定钾分解活化为有效钾 ,被玉米吸收利用 ,促进其根系发育 ,苗全秆壮 ,增强抗倒伏性能 ,同时增强植株光合作用 ,促进碳水化合物的形成和积累 ,增加产量